Sea Water Thermodynamic Properties?

Im looking for thermodynamic properties of seawater, especially specific heat and enthalpy. Im designing a solar desalinator, and im trying to determine the required amounts of energy to evaporate the water.

Is there a way in which I can determine the enthalpy of seawater by knowing the enthalpy of both salt and water?

Kaiser Engineering did an extensive research study for the government on the thermodynamic properties of seawater about 40 years ago. The properties vary with the salinity, which also varies in different parts of the seas. It is available from the Library of Congress